As we kown, PCB material classification is mainly the following: FR-4 (glass fiber cloth base), CEM-1/3 (glass fiber and paper composite substrate), FR-1 (paper based copper clad plate), metal base copper clad plate (mainly aluminum, a few iron base) more than the current more common types of material, generally known as rigid PCB. Among them, FR4 is the most common material. The FR4 material is usually TG 130. More than 130, we call it special pcb material.More common ones：single side PCB，double side PCB，multilayer PCB，High TG PCB multilayer，Copper Base PCB.PCB Circuit Board is the foundation of current electronic and electrical industry, which contributes a lot to the progress of technology.